I've been running the Odyssey PC680MJT batteries in both 1200's. One has been in use for a year, the other has been in 2 years. 220 CCA, very small, and 15#.

http://www.summitracing.com/parts/ODY-PC680MJT/

JDM battery as fitted to many new cars:


Height: 20.4 mm (7-7/8 inch)
Width: 18.8 mm (7-3/8 inch)
Depth: 12.8 mm (4-7/8 inch)
Weight with acid: 9.7 kg (21.4 pounds)
CCA: 274
Capacity @ 20 Ah: 33-35
Reserve Capacity Minutes: 52

Battery

Group 26 battery is a lot lighter (only 31 pounds) and more powerful than the original specification.

got any pictures? :)

For a stocker A12 a 350CCA lead acid battey should be more than enough, and they are about the same size as in the pic.

Im sure you could run with a 280cca or less, but you would want to make sure it starts easy all the time. One carby flood and 30 seconds on the starter would drain a small battery pretty quick.

The Calcium-calcumim hybrid batterys seem to about the best ive found for compact power, but they are alittle pricy. I got a 3 year warrenty with all the ones ive bought, (350cca and 800cca units), so i reckon they are good value.

I dunno the size. I went to sears and bought their smallest automotive battery which is group 26.

Next time I will go to Walmart and buy a lawn tractor battery. Some guys run those in their 1200s with no problem.

I was thinking of putting one close to the firewall. As my car is LHD and has a front distributor there's a little extra room there. Allowing for a little 'mass centralization'. What size battery is this?

mines is about half a foot in front of my rear left wheel, pain in the arse to get to

farther back than normal. These are a good size battery for an A-series engine (a bit larger than the JDM battery). Guess you could fit one just about anywhere.